diff --git a/surfsense_backend/tests/unit/services/okf/test_ingestion.py b/surfsense_backend/tests/unit/services/okf/test_ingestion.py
new file mode 100644
index 000000000..e7c49bc33
--- /dev/null
+++ b/surfsense_backend/tests/unit/services/okf/test_ingestion.py
@@ -0,0 +1,31 @@
+"""A ConnectorDocument (the indexing write door) must serialize to a valid OKF
+concept. Per-``DocumentType`` conformance lives in ``test_conformance.py``.
+"""
+
+from app.db import Document, DocumentType
+from app.indexing_pipeline.connector_document import ConnectorDocument
+from app.services.okf import document_to_concept, is_conformant_concept
+
+
+def _document_from(connector_doc: ConnectorDocument) -> Document:
+    """Mirror how prepare_for_indexing builds a Document from a ConnectorDocument."""
+    return Document(
+        title=connector_doc.title,
+        document_type=connector_doc.document_type,
+        source_markdown=connector_doc.source_markdown,
+        document_metadata=connector_doc.metadata,
+    )
+
+
+def test_minimal_connector_document_yields_conformant_concept() -> None:
+    connector_doc = ConnectorDocument(
+        title="Bare",
+        source_markdown="just a body",
+        unique_id="u1",
+        document_type=DocumentType.FILE,
+        workspace_id=1,
+        created_by_id="user-1",
+    )
+    doc = _document_from(connector_doc)
+    concept = document_to_concept(doc, body=doc.source_markdown)
+    assert is_conformant_concept(concept)